Hollow concrete floor construction.



WITNESSES:

M. KHNB.

HOLLOW CONCRETE FLOOR CONSTRUCTION.

APPLICATION FILED 0cT.4,191a,

Patented Dec. 1,1914.

3 SHEETS-SHEET l.

/Nvmron Mariah ffii/1n e.

M.KHNB

HOLLOW CONCRETE FLOOR CONSTRUCTION'.

APPLICATION FILED OCTA, 1913.

1 ,1 19,435, Patented Dec. 1,1914.

3 SHEETS-SHEET 2,

fly. 4.

M. KHNE.

HOLLOW CONCRETE FLOOR CONSTRUCTION.

APPLICATION FILED CCPA. 1913,

Patented Deo. 1, 1914.

3 SHEETS-SHEET 3,

gmhwmwmum u UhUmUm' v IN1/5mm? Martin Khne'.

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@In ntnnnyon PORTLAND, oREGoN application ined ctober 4, 1913.

unsern known l., Marian KHNE, a of the United State-s, and' a resident ne city oi' Portland, county ofvil/iultno- State of Gregor., have invented a. new useful improvement in Hollow Con. d Floor onstructioinof which the folug is a .Speciication 'nvention relates to the modern conn of concrete iloors, referringin par to that construction which involves ig or hollow or air spaces in the ..-oor slabs; and my invention has ibject the providing of forms, or cen- .ich combine maximaleiliciency with l cost of manufacturing and putting irrt-her object of my invention is to `means for joining the adjacent i' practical and eilicient manner;

o suspend the metal. ceiling lathin a cure manner by means not dependable on lreys formed by the concrete in the opens ot the metal lath.

forms with few stiiiening ribs or elements lpossible, butv so form these ele ments as to safely carry all the loadv that may be imposed on the form; also, to avoid lo any sagging in the field or web at the top of torni. and thus prevent the undesirable consequences due to lsuch defect.

The several features of my invention are more readily understood by describing in the rst instance the accompanying drawings,- in which:

Figure 1 is a. longitudinal section of a concrete iloor slab embodying my invention; Fig. 2 is a top view of the forms used in the construction of such floor slab, also showing 'he bridges connecting adjacent "forms, and the metal ceiling lath as independently suspended from such bridges and the reinforc-A ing bars supported by the latter; Fig. 3 is a perspective detail of one of the bridges connecting adjacent forms; Fig. 4 is a perspec tive view showing a section of a. fioor slab` Awith part of the concrete removed so as to show all of the metal reinforcing parts entering into such construction; Fig. 5 is a top view similar to Fig. 2, except that the form is of different construction than shown in Eig. 2; the particular form here shown be.- ing four-sided and embodying other details which will be fully described in the body of the specification; Fig. 5 is a vertical section Specification of Letters Patent.

ifs further object of .my invention is to make Serial No. ''93,474.

taken along the right-angular line A-*A of Fig. 5; this ligurealso'showing some of the concrete mass; and Fig. 7 is a. detail or" `construction hereinafter fully explained.

Referring in the first instance to the illus. tration of my invention in Figs. 1 to 4 inclusive: b represents the metal ceiling lath, and ai the bridges connecting adjacent forms z'. The type of form here shown comprises a 'sheet metal structure having sides and an arched top, The latter is made with pressedout ribs or primary stiening elements j, protruding outwardly from the body of the form,` as more clearly seen in Fig. l. The primary' ribs y' are bent outwardly, as inentioned, so as to impart maximum inherent resisting power to the metal form with respect to the Weight of the concrete mass poured over the form. In the flat fields or webs between' the primary ribs j are formed a plurality of transversely disposed supplemental ribs or stiiiening elements lo, also pressed outwardly, as more clearly shown in Figs. l and Said supplemental ribs have a transverse enlargement maximal midway between the adjacent primary ribs, so as t0 have their greater sustaining power at that point, and adapt them to safely take care of any stress which the field or Aweb between the primary ribs may have to sustain. My reason for the described particular construction of said supplemental ribs is this: Midway between the primary ribs there is greater stress imposed by the weight of the concrete mass than close to such ribs. Hence unless efficient means are provided for taking care of this stress there would-be a tendency for said intermediate field or web to sag at said midway point, which sagging would tend to aggravate the circumstances; for it would form a pocket in which an abnormal quantity of material is reposed, thus imposing further weight'upon the sagging field, and. besides, causing a waste of the concrete lilling the pockets formed by such saggcd places. and in so doing unnecessarily increasing the cost of the building.

The bridges Z are formed of sheet metal and have their ends e made V-shaped, or ot' channel torni. so as to receive the sides t" oi the forms. as shown in Figs. 1 and 4. rlhe bridges d rest on the metal ceiling lath J). To prevent them from sagging. due to the weight of the concrete mass poured on them. l provide each bridge with a leg g. This leg is preferably pressed out of the Patented Dee. 1, 1914.'

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g mmm belly 'nf the brfg@ @arranged expend-inularly to the body, and eer-v as e ati means for 'the bedy',"l)esen snppertng The leg q is disposed diagonally to the nails; of the bridge-body,vso as .to insure that tlm legfg. will, stradd1e the cut-out sp fb of themetal 'ceiling lath under all 'con 'tiuns, and thus servev as a dependable support for the lcenter ofthe bridge.

Reinforcng #bars f are plaeed on `the bridges, as shown, andthe metal celin lath' is wired to said reinforcing bers, as s own ath, `and'rnay alsobe tel the bridge', as shown at h in''Fg. My piarpese in so wanting the metal latlx this: n.. case! of fire, the cement keys might be insnc-ient to hold thefeeling lath in plu-ee,- Whle havingjthe ceiling* luth ifastenecl to the ren-- forcing bars they are supported independently of the' concrete mass and render the Hoor much more. durable even in a severe re. l

The ,primary ribS 'j extend 'with the are and slope upwardly to the apex j, so as to give maximum strength. to rey-form.'

' In the other type of my forms or centers, illustra-ted in Figs. 5 and {L} the eatures not changed are. designatec by the same lettere as desi .ate like parte in preceng 5g# ures. A s mentioned? this type of my formarched so as "to come to the apex r, thus producing the same effect here as at in the other types o my form. n the flat fields between the hipe or primary stilening ele;

ments q are presse out supplemental ribs or stl'enmg elements n? made with a trans- Ving at the verbe enlargement toward that "point of thel elcl where' the prxmary stlffemng elements are wlest apart. lln orrer to make these forms-i of great strength, prefer also to Imake the finies witn pressedmnt vvertleal ribew et, 0

I claim:r` v y v1. A. floor-form made of non-corrugated -sheet metal, having primary, deep stieninribs pressed out, and supplenlental, deep sti enng-rbs pressed out between the primary stiifening nbs; said supplemental stiifening ribs being arched in Varying cross section with' the .greater span midway between the primary Stifening ribs and tapering at the enel. toward diie latter. 2,' A loor-orm made el? non-corrngate sheet metal, having primardeep sti'eningribs' pressed out and extended parallel to each 'other-fn line direction", and supplemental,

deep stiening-ribs pressed out between the primary stxfenmg mbe; sani supplemental stllfezung'mbs'belng arched m varyltng cross o nary sening ribs; and tapers toward 1lilater. l. EL loerxrm mede non-corrugated tween the 'sheet metal, keying; primary, deep stillenngibs pri-seed ont and extended parallel to each ether 1n one dlreetmn, and suppletween ered 'perpendicular to the primary stenng ri'fee; seid Supplemental stifening ribsbeing nrc-neel in varying cross section with the greater spgm, midway between the primary Stilenng ribs and tapering at the enfle toward the latter.

MARTIN KHNE.-

llfitnesses:

WM. C. SGHMIIT Cnam Lons.

'Setion 'with the greater span midway be- 

